Valve for the control of hydraulic presses



Oct. 29., 1940.

M. R. LIEB ET AL 2,219,843

VALVE FOR THE CONTROL QF HYDRAULIC PRESSES Filed June 22, 1938 4Sheets-Sheet l Attorneys Inventor- Oct. 2 1 4 M. R. LIEB El AL VALVE FORTHE CONTROL OF HYDRAULIC PRESSES Filed June 22, 1938 4 Sheets-Sheet 2Inventors .2179; 229.27-

r716 11671756192071 M By fin w $5 A iiorneys M. R. LIEB ET AL VALVE FORTHE CONTROL OF HYDRAULIC PRESSES 4 Sheets-Sheet 3 Filed June 22, 1938Lnl Inventors Oct. 29, 1940. M. R. LIEB El AL VALVE FOR THE CONTROL OFHYDRAULIC PRESS-ES Filed June 22. 1958 4 Sheets-Sheet 4 I In veniorsAttorneys Patented Oct. 29, 1940 VALVE FOR, THE CONTROL OF HYDRAULICPRESSES Merril R. Lieb, Allentown, and Walter W. Wassum,

Alburtis, Pa. 1

Application June 22, 1938, Serial No 215,244

' 1 Claim.

This invention relates to valves for controllin the fluid pressureemployed for the operation of hydraulic presses and of the character setforth in our copending application Serial No. 176,322

and filed November 24, 1937, now Patent No.

2,152,551, granted March 28, .1939, and has for the primary object theprovision of means for increasing the efiiciency of the device bybalancing the pressure against the pressure control valve elements ofthe valve either when closed or opened so as to require less power forthe operation or movement of said valve elements to their difierentpositions.

Another object of this invention is the provision of means whichimproves the valve elements to prevent leakage of pressure either whenclosed or opened.

With these and other objects in view, the invention consists in certainnovel features of construction, combination and arrangement of parts tobe hereinafter more fully described and claimed.

For a complete understanding of our inVen-' tion, reference is to be hadto the following description and accompanying drawings, in which Figure1 is a vertical sectional view illustrating a valve constructed inaccordance with the present invention.

' Figure 2 is a topplan view illustrating the same.

Figure 3 is a sectional view taken on the line 3-3 of Figure 1 lookingin the direction indicated by the arrows.

Figure 4 is a sectional view taken on the line 4-4 of Figure 1 lookingin the direction indicated by the arrows.

Figure 5 is an end view illustrating one end of the body portion of oneof the valve elements.

Figure 6 is a sectional view taken on the line 66 of Figure 5.

Figure 7 is an end view illustrating a valve head detachably securedonthe body portion of the valve element.

Figure 8 is a sectional view taken on the line 88 of Figure 7.

Figure 9 is a diagrammatical view illustrating passages in the valve andthe connection of said passages to opposite ends of a cylinder forming apart of a hydraulic press (not shown).

Referring in detail to the drawings, the numeral Ill indicates a powercylinder forming a part of a hydraulic press (not shown) While thepiston of said cylinder is indicated by the character II and is adaptedfor reciprocation in the cylinder under fluid pressure. The ends ofthecylinder have connected thereto pipes I2 and I3 for admitting andexhausting fluid pressure to said cylinder I0 for the reciprocation ofthe piston. The pipes I2 and I3 are connected to a valve I4 forming thesubject matter of the present invention.

The valve I4 includes a body I5 in which are arranged pairs ofvertically disposed chambers I6 for the reception of pairs of valveelements I! and I8. The valve elements ll are for controlling fluidpressure from a source to the ends of the cylinder I0 and the valveelements I8 are for controlling fluid pressure from the cylinder Illback to the supply or to the atmosphere. The valve elements II will behereinafter known as pressure control valves while the valve elements I8will be known as return valves. The valveelements H are diagonallyarranged to each other also the valve elements I8 are diagonallyarranged to each other and are adapted for reciprocation in theirrespective chambers I6 which open outwardly through the top wall of thebody I5 and have threaded therein packing gland sleeves I9 engageablewith packing 20 to force said packing against the valve elements toprevent leakage. Mounted in thechambers 16 are valve seats 2I. Each ofthe valve elements has its inner end shaped or designed to form asubstantially U-shaped flange 22 to receive a grooved head 23 of a seatengaging element 24. The element 24 has a beveled face 25 to engage witha seat 2I and also includes a skirt 26 slidable within the walls of thesleeve. The skirt below the face 25 has a series of ports 21 which willpermit a flow of fluid through the skirt when the face 25 is disengagedfrom the seat.

The seat engag ng elements 24 may be readily" detached from the valveelements I'I'and I8 when the'latter are removed from the chambers I6.However, said seat engaging elements are prevented 'from becomingaccidentally disconnected from said valve elements I1 and I 8 when thelatter are mounted for operation in the chambers I6 due to the factthatthe skirts 26 always remain in contact with the seats 2| or thewalls thereof during all positions of the valve elements.

- Thevalve elements I8 include elongated cylindrical portions for thepacking 20 to engage and reduce screw threaded portions 28 arranged eX-teriorly of the body for connectionwith an operating means which will behereinafter more fully described. The valve elements I! includecylindrical portions 30 and ill of diiierent external diameters. Thecylindrical portions 3| of the valve elements I-I provide piston-likeportions thereto and are engaged by packings 32 arranged in the chambers6 of the valve elements I! between the packing gland and seat 33provided therefor. The packings 32 also engage with the cylindricalportions 30 of the valve elements |1. Between the packing gland sleevesIQ of the chambers |6 which receive the valve elements l1 and thecylindrical portions 3| are formed pressure chambers 34. The pressurechambers 34 below the cylindrical portions 3| are open to the atmosphereby vents 35 provided in the body I5 of the valve. The valve elements l1also include reduced screw threaded portions 28 to permit said valveelements I1 to be connected with the operating means.

The body |5 of the valve has fluid chambers 36 which are located in thechambers |6 of the body and in which the valve seats 2| are located. Thefluid chambers 36 extend above and below the valve seats. The lowerportions of the fluid chambers 36 of the valve elements l1 are connectedto the pressure chambers 34 by bypass pipes 31.

The purpose of the bypass pipes 31 is to permit equal fluid pressure tobe had between the lower portions of the fluid chambers and the pressurechambers 34.

Formed in the body l5. of the valve is an intake passage 38 connectingwith the .upper portion of the-fluid chambers 36 of the valve elementsl1 and with a fluid pressure source (not shown). The body of the valveis also provided with an exhaust passage 39 connecting withthe lower endof the fluid chambers 36 and opening outwardly of the valve body to theatmosphere or may besuitably connected with the fluid pressure sourcefor the return of fluid thereto. The valve body is provided with portsor passages 46 connecting with the lower portions of the fluid chambers36 of the pressure control valve elements l1 "and one of the ports 40 isconnected to one end "copending application filed on even date with theare secured on the shafts 49.and are pivotally 01. 7 of the shafts 49with the valve elements l1 and I8 other and the valve elements I8reciprocated inof the cylinder ID by a pipe 4| whilethe other port 40 isconnected to the other end of the cylinder It! by a pipe 4|. Passages 42connect the .,lower portions of the fluid chambers 36 of the 'pressurecontrol valve elements H to the upper ,nect the fluid chambers 36 insuch a way that fluid may flow between the fluid chambers of the valveelements I 1 and |8 that are arranged in opposite pairs.

The operating means indicated in entirety by the character 43 forms thesubject matter of a filing of this present application and will bebriefly set forth herein for the purpose of giving a clear understandingas to the operation of the present invention. k A saddle 44 is mountedon the body of the valve and slidably supports blocks 45 secured on theportions 28 of the valve elements l1 and I8 by nuts 46. The blocks 45are provided with notches 41 to receive teeth or ribs 48 on shafts 49journaled in the saddle 44. Arms 50 connected to an operating lever 5|by linkage'52. Pivotal movement of the operating lever 5| in oppositedirections brings about rotation of the shafts 49 in oppositedirections. The connection is such that the valve elements will besimultaneously reciprocated and the pair of valve elements |1recip-rocated in opposite direction to each opposite direction to eachother. Thus it will be seen that when one of the valve elements I1 is ina seated position the other valve element will be in an unseatedposition which also applies to the valve elements IS. A movement of theoperating lever 5| in one direction unseats one of the valve elements Hand one of the valve elements It which permits a flow of fluid pressurefrom the source (not shown) to one end of the cylinder while theopposite end of the cylinder is exhausting. The flow of the fluid isindicated by the arrows in Figure 9 entering the passage 38 to the upperportion of the fluid chambers 36 and as one of the valve elements I1 isunseated fluid flows past the seat into the lower portion of the fluidchamber 36 of said unseated valve element l1 and through the pipe 4| toone end of the cylinder l0, thereby forcing the pistion to the left inFigure 9. The fluid to the left of the piston l leaves the cylinder II]by way of the pipe 4|, enters the lower portion of the fluid chamber 36of the seated valve element |1 through one of the passages 42 to theupper portion of the fluid chamber 36 of the unseated valve element 8and downwardly past the seat 2| thereof to the exhaust passage 39 whencethe fluid may exhaust to the atmosphere or return to the fluid pressuresupply through the medium (not shown) if connected to the exhaustpassage 39. The flow of the fluid is reverse to that just described andindicated by the arrows in Figure 9 when the operating lever 5| is movedin an opposite direction to bring about movement of the piston II in thecylinder Hi to the right in Figure 9.

Due to the arrangement of the passages and ports as described in detailand their connection with the fluid pressure source the upper portionsof the fluid chambers 36 of the pressure control valve elements H arealways in direct communication with the fluid pressure source so thatthe pressure of the fluid will act in an upward direction on the lowerends of the valve elements l1 and also on the seat engaging elementsthereof in a downward direction which brings about a balanced pressureon the valve elements l1, consequently-permitting the valve elements Hto be moved oif of their seats with a minimum amount of force appliedthrough the actuation of the operating means 43. Due to the connectionbetween the seat engaging elements and the bodies of the valve elements|1 spaces are provided therebetween which permits the fluid pressure toact in opposite directions on the valve elements so that a minimumamount of force is only necessary to unseat the valve elements l1. Whenthe valve elements H are unseated the fluid pressure then becomes equalthroughout the entire areas of the fluid chambers 36 of the valveelements H. The fluid pressure then may enter the chambers 34 by way ofthe bypass pipes 31. The fluid pressure is then acting on the valveelements IT in opposite directions bringing about floating of the valveelements |1 While unseated, consequently requiring only a minimum amountof force to move the valve elements l1 from unseated position to seatedposition. The fluid pressure in the chambers 34 acts upon thecylindrical portions 3| of the valve elements H in a downward directionwhile the fluid pressure in the upper portion of the fluid chambers actson the valve elements .|1 in an upward direction bringing about floatingof the valve elements |1 when unseated. Thus it will be seen that itwill require very little forcein the movement of the valve elements H ineither direction and as the valve elements 18 are only subjected to lowfluid pressure, the operation of the valve can be brought about with aminimum amount or expenditure of manual effort or fluid pressure if theoperating lever is so actuated.

It is believed that the foregoing description, when taken in connectionwith the drawings will fully set forth the construction and advantagesof this invention to those skilled in the art to which such a devicerelates, so that further detailed description will not be required.

Having thus described the invention what we claim is:

In a valve, a body provided with an elongated bore having diflerent sizedimensions to form a shoulder within said bore, one end of said boreopening outwardly through a face of the body and the other end beingprovided with a fluid pressure exhaust, a stufling box removably andadjustably mounted in the first-mentioned end of the bore, a seat in thebore and spaced from said shoulder and the fluid pressure exhaust,packing located in the bore and bearing against the shoulder and thestufling box and having contact with the walls of the bore from theshoulder to the stufling box, a slidable valve element in said bore andhaving valve opening and closing positions and including a stemslidable-through the stufiing box and a piston and a plunger integrallyconnected and having slidab-le fit with the packing, said packing andseat defining therebetween a fluid pressure chamber; in the bore with aportion of the plunger therein, means for admitting constant fluidpressure to said chamber, said packing, piston and stufling box coactingto form a second fluid pressure chamberin the bore, operating meanslocated exteriorly of the body and connected to the stem for sliding thevalve element in opposite directions to engage and disengage the plungerwith the seat, said piston having an area exposed to thesecond-mentioned fluid pressure chamber equal to-the area of the plungerexposed to the first fluid pressure chamber when said plunger isdisengaged from the seat, and a bypass pipe connecting the firstnamedfluid pressure chamber to the fluid pressure exhaust for admitting fluidpressure from the first-mentioned fluid pressure chamber to thesecond-mentioned fluid pressure chamber when the plunger is disengagedfrom the seat for balancing the valve element when in valve openingposition.

MERRIL R. LIEB. WALTER W; WASSUM.

